How to use NISS in FMC - an intuitive explanation

An intuitive explanation of NISS (Normal-Inverse Scramble Switch) that I gave for a viewer while streaming on Twitch.
Join me Thursday 3/22 at 2PM PT for my next stream! www.twitch.tv/kitstopher
Below is an explanation of the end part again, because I kind of skipped a part of the argument in the moment:
We know that this sequence produces a solved cube (S):
(N2)' (N1)' (I) (I1) (I2) = (S)
We could clearly perform all of the moves on the left hand side in the reverse order, and still get a solved cube:
(I2)' (I1)' (N) (N1) (N2) = (S)
Now, before applying this sequence on the left that just leaves a solved cube, we could perform I1, then I2. This cancels with the inverses on the left:
(N) (N1) (N2) = (S) (I1) (I2)
But the "S" is redundant here, since no moves are applied to leave a solved cube as a solved cube:
(N) (N1) (N2) = (I1) (I2)
Now, consider performing to these equivalent cube states (I2)', then (I1)':
(N) (N1) (N2) (I2)' (I1)' = (I1) (I2) (I2)' (I1)'
On the right hand side, you are simply undoing the moves already done. This leaves a solved cube!
(N) (N1) (N2) (I2)' (I1)' = (S)
Thus, after performing the normal scramble, the move sequence (N1) (N2) (I2)' (I1)' results in a solved cube! Thus, it is a valid solution.

[@felix-lk7ic]

Thank you so much for making this!

[@LazyEinstein]

I like the part where the example cubes are circles.

[@SolomilloDeJerez]

It's a spherical cube in vacuum.

[@rayquazapwn88]

I've used NISS in my countless 69 move solutions but I finally know how it really works.

[@MimeDuck]

are you brandon mikel

[@dah1abills]

Love the explanation!

[@pou4447]

I cant write the solution any tips pls

[@miacubing]

Nice!